Global animal tracking system Icarus is switched on

The German-Russian observation system for animal movements, Icarus, will go into operation on 10 July 2019. In the subsequent test phase, the Icarus engineers and scientists will check the system components on the ground, ...

A wearable vibration sensor for accurate voice recognition

A voice-recognition feature can be easily found on mobile phones these days. Oftentimes, we experience an incident where a speech recognition application is activated in the middle of a meeting or a conversation in the office. ...

Britain to intensify fight against climate change

Britain's outgoing prime minister on Wednesday announced plans to eliminate the country's net contribution to climate change by 2050 as Europe's effort to slow global warming picked up speed.

Nanoscopic protein motion on a live cell membrane

Cellular functions are dictated by the intricate motion of proteins in membranes that span across a scale of nanometers to micrometers, within a time-frame of microseconds to minutes. However, this rich parameter of space ...

Engineers design solutions to tackle low-frequency noise

Low frequency noise (500 Hertz and lower), which could stem from various sources such as construction machineries and aircrafts, is a form of environmental noise problem in urban environments. Such noise transmits over long ...

Restaurant acoustics that schmeckt

Acoustics consultant Klaus Genuit says that new International Standards Organization guidelines for defining, measuring and evaluating soundscapes are a big step forward in guiding the creation of audibly fine restaurants.

Signals to noise in acoustic vehicles alerting systems

If you've ever wished for a quieter commute, you may be in luck: The low-emission electric vehicles of tomorrow are expected to lower noise pollution as well as air pollution. In Europe, and across the world, the prospect ...

page 1 from 23

Noise

In common use, the word noise means any unwanted sound. In both analog and digital electronics, noise is random unwanted perturbation to a wanted signal; it is called noise as a generalisation of the acoustic noise ("static") heard when listening to a weak radio transmission with significant electrical noise. Signal noise is heard as acoustic noise if the signal is converted into sound (e.g., played through a loudspeaker); it manifests as "snow" on a television or video image. High noise levels can block, distort, change or interfere with the meaning of a message in human, animal and electronic communication.

In signal processing or computing it can be considered random unwanted data without meaning; that is, data that is not being used to transmit a signal, but is simply produced as an unwanted by-product of other activities. "Signal-to-noise ratio" is sometimes used to refer to the ratio of useful to irrelevant information in an exchange.

In biology, noise can describe the variability of a measurement around the mean, for example transcriptional noise describes the variability in gene activity between cells in a population.

In many cases, the special case of thermal noise arises, which sets a fundamental lower limit to what can be measured or signaled and is related to basic physical processes described by thermodynamics, some of which are expressible by simple formulae.

In some fields, noise means unwanted information or data that is not relevant to the hypothesis or theory being investigated or tested.

This text uses material from Wikipedia, licensed under CC BY-SA